What would happen if voting by mail became compulsory? Laws allowing no excuse absentee voting are on the books in twenty-nine states. Enhanced voting options appear to be popular among voters; in the 2008 presidential election more than one-third of the electorate voted early, and in California's May 2009 statewide election a record 62.19% of voters cast their ballots by mail. These participation rates are notable, but in all but two states casting a ballot by mail is optional. As such, voters chose to cast their ballot by mail, thus the participation data are based on self-selected behavior. What would happen to registrants when they have no choice and are required to cast their ballot by mail? We answer that question in this article. In this study we exploit a natural quasi-experiment in California to test how the utilization of mail-only balloting affects the turnout of registrants. We analyzed the behavior of 97,381 individual voters across four elections from 2006 to 2008 and found that when all-mail balloting was implemented, the estimated odds of an individual registrant voting decreased by 13.2%.

Introduction

What is the impact of vote by mail on individual registrant turnout? That is a question election administrators and policymakers alike are grappling with across the country as more and more states consider moving to some form of vote-by-mail system. For now, Oregon remains alone in conducting all elections by mail. In Washington all but one of its counties vote by mail. Montana allows vote by mail for municipal elections, and Idaho and New Jersey have taken steps in that direction. California and Colorado already permit permanent no excuse absentee ballots, and twenty-nine states have provisions for no excuse absentee voting.

Tournout rates from recent elections show that voters are taking advantage of laws that provide options for how they cast their ballot. For example, in November 2008 more than a third of the electorate voted early, up from 15% in 2000 and 22.5% in 2004.